NUTDEF is an interactive computer program to aid in determining the specific nutrients or combination of nutrients causing nutrient deficiency symptoms in landscape plants. It has been written in Turbo Pascal for use on microcomputers.

sulfur, calcium and molybdenum are not as mobile in plants and deficiency

symptoms are first seen on new growth.

Another important step in symptom evaluation is to determine if the

symptoms can be characterized by some pattern of leaf chlorosis.

Phosphorus, boron, molybdenum, and copper deficiencies generally do not

result in leaf chlorosis during early stages of symptom development.

This is an important criteria upon which several of the nutrient

deficiency symptoms can be separated.

The pattern of leaf yellowing or chlorosis is also an important clue

in determining which nutrient is deficient. For example, a primary

symptom of iron and manganese deficiencies is interveinal chlorosis. An

iron deficiency results in a network of fine green veins on the yellow

leaf, and a manganese deficient leaf has larger green veins during early

stages of symptom development.

Before NUTDEF is accessed, the user should either obtain a fresh

sample of the plant in question or become extremely familiar with the

symptomology of the plant. It would be difficult to respond correctly to

the questions posed by this computer program unless the user has a sample

in hand or frequently evaluates plant symptoms.

Figure 1. Nutrient deficiency symptoms on azalea leaves.

EXAMPLE RUN #1

Turn on the computer and load the operating system (MS-DOS for IBM).

Insert the program disk into the disk drive and type NUTDEF. The credits

are presented first on the screen and the user can press any key to

continue to the second screen where a choice is given to view an abstract

or initiate the execution of the program immediately. The following

statement will appear on the screen.

Do you want to read the abstract?

Enter Y for yes or N for no

After the abstract has been viewed or skipped, the user must respond

to several questions. The disk drive in. which the NUTDEF program disk

has been loaded must first be identified. The question will be presented

on the screen as follows: ... .

In which drive are your NUTDEF program files located?

Enter A or B or C

The user would press the appropriate letter and NUTDEF would

continue.

For this example run, we wish to determine the nutrient deficiency

causing the symptoms on the azalea in Figure 1. The user must first

determine if the symptom appeared first on young or mature foliage. The

question will be presented on the screen as follows:

Please choose the statement below that best describes the
symptoms of the plant in question.

A:
Symptoms appear on the youngest leaves first.

B:
The entire plant is affected or the oldest leaves
are affected first.

Please enter the letter corresponding to the most accurate
statement (A or B). ?

In this example the symptoms appear on the younger leaves of the

azalea plant, therefore the user would press the letter A (upper or lower

case).

The user must next determine if the primary characteristic of the

symptom is leaf chlorosis. The following question will be displayed on

the screen.

Please choose the statement below that best describes the
symptoms of the plant in question.
A: .-.
The dominant symptom is chlorotic foliage.
B:
Leaf chlorosis is not the dominant symptom.

Please enter the letter corresponding to the most accurate
statement (A or B). ?

Since the dominant symptom of the azalea in Figure 1 is chlorotic

foliage, the user should enter A.

The leaf chlorosis on the azalea in this example must be more

clearly defined in order to distinguish between the characteristics of

the chlorosis caused by several nutrient deficiencies.. The following

questions appear to aid the user in defining the chlorosis.

Please choose the statement below that best describes the
symptoms of the plant in question.
A:
Terminal growth is generally chlorotic or appears
pale yellow.
B:
Terminal growth exhibits interveinal chlorosis,
meaning the veins remain green while the rest of the
leaf surface is yellow.

Please enter the letter corresponding to the most accurate-
statement (A or B).?

Press the letter B to indicate the interveinal chlorosis of the plant in

this example.

The features of the interveinal chlorosis must be more clearly

defined. The following options are presented to the user to aid in

defining this symptom.

Please choose the statement below that best describes the
symptoms of the plant fn question.
A:
Interveinal chlorosis results .in leaf veins appearing
as fine green lines on a pale yellow to ivory colored
surface. In advanced stages the leaves are entirely
cream colored and dwarfed. Tip and marginal leaf
burn is possible.
B:
Early stages of interveinal chlorosis result in
relatively wide areas of green associated with the
veins. Contortion of plant parts such as leaves,
shoots, fruits or stems is also possible.
C:
There is a characteristic reduction in leaf size, up
to 95% reduction in leaf size is possible in severe
cases. Leaves may be very narrow with smooth or wavy
margins. One side of the leaf may not expand as
much as the other side, resulting in a puckered leaf.
Shorter internodes may result in tufts of abnormally
small, pointed leaves and shoots called "rosettes".

Please enter the letter corresponding to the most accurate
statement (A, B or C). ?

The user would press A in this example to indicate the characteristics of

the interveinal chlorosis.

The computer program now has enough information to determine the

probable nutrient causing the symptoms. The following statement will be

displayed on the screen.

There is probably a deficiency of IRON in this plant.

Press any key to continue?

After the user has pressed any key to continue an opportunity is

given to identify the possible nutrients) causing deficiency symptoms on

another plant. If the user was unsure about a response make during the

previous set of questions, now would be the appropraite time to execute

the program again giving the alternative responsess. The following

question is displayed on the screen.

Would you like to identify another nutrient deficiency

symptom (Enter Y for yes or N for no)?

If the answer is no, press N and the following statement will be

displayed. The $ prompt will indicate the user has been returned to the

MS-DOS operating system.

This concludes your session with NUTDEF

Have a nice day !

$

If the user answers yes to the above question, the first screen to assist

the user in identifying the symptom is displayed.

EXAMPLE RUN #2

The Pittosporum tobira with a nutrient deficiency symptom in Figure

2 will serve as the sample for Example #2. The first two displays

presented to the user will be the same as in Example #1. The first

question is presented as follows:

Please choose the statement below that best describes the
symptoms of the plant in question.
A:
Symptoms appear on the youngest leaves first.
B:
The entire plant is affected or the oldest leaves are
affected first.

Please enter the letter corresponding to the most accurate
statement (A or B).

In this example the symptoms appear on the older leaves of the

pittosporum plant, therefore, the user would press B.

The user must next determine if the primary characteristic of the

symptom is leaf chlorosis. The following question will be displayed on

the screen.

Please choose the statement below that best describes the
symptoms of the plant in question.
A:
The dominant symptom is chlorotic foliage.
B:
Leaf chlorosis is not the dominant symptom.

Please enter the letter corresponding to the most accurate
statement (A or B).

Since the dominant symptom of the pittosporum in Figure 2 is
chlorotic foliage, the user should enter A.

Nutrient deficiency symptom on Pittosporum tobira.

Figure 2.

The leaf chlorosis on the pittosporum in this example must be more

clearly defined in order to distinguish between the characteristics of

the chlorosis caused by several nutrient deficiencies.

The fol 1 owing

questions appear to aid the user in defining the chlorosis.

Please choose the statement below that best describes the
symptoms of the plant in question.

A:
A uniform loss of green leaf coloration is the first
symptom to appear. In advanced stages the leaf color fades
to almost ivory and the leaves become thick, brittle, small
in size and fewer in number. Eventually, the entire plant
is stunted, sparsely foliated and growth slows
dramatically.

B:
Leaf chlorosis on the older foliage is initially
interveinal. As the deficiency becomes more severe,
chlorosis of new growth, intervenal speckling or browning
and margin leaf scorch develops. Irregular dead spots on
the leaves may occur. Entire limbs may die.

C:
Bronze or chlorotic areas are irregular in outline and
occur in irregular blotcKes between the midrib and main
lateral veins toward the middle of the leaves. Chlorotic
areas advance to leave an inverted green "V" at the base of
the leaves, but this pattern differs with leaf structure.

Please enter the letter corresponding to the most accurate
statement (A, B or C).

The distinctive "V" at the base of the leaves indicates that option C

would be the most appropriate answer, therefore the user would press C.

The program now has enough information to give the probable nutrient

that is deficient and the following statement would be displayed.

There is probably a deficiency of MAGNESIUM in this plant.

Press any key to continue?

The user is then given the option of identifying another nutrient

deficiency symptom or terminating the session with NUTDEF as indicated in

Example # 1.

Often more than one nutrient deficiency occurs on the same plant at

the same time. This makes identification of the nutrients more

difficult. Common deficiency combinations include iron and manganese,

zinc and copper, and iron, zinc and'copper. Often these multiple

deficiencies have the overall appearance of an iron and/or manganese

deficiency but application of one element may not totally correct the

disorder. Symptoms of one nutrient deficiency can mask one or more

nutrient elemental deficiencies, which will become evident when the

dominant deficiency is corrected. Application of materials containing

all the micronutrients may be the best approach if a single micronutrient